Why was the global flag disabled for cross domain script type $.ajax requests in older versions of jQuery

Why was the global flag disabled for cross domain script type $.ajax requests in older versions of jQuery

I'm using jQuery 1.12 and I noticed my global ajax event handlers (`ajaxSend`, `ajaxStart`, etc) weren't running for `$.ajax` requests with `dataType="script"` and `crossDomain=true`.  After some investigation I found that in 1.12, jQuery always disabled the global flag on the request if it the dataType is script and it's cross domain!

What was the reason for this behavior?  Why was it originally added and why was it later removed?

Relevant information:
  1. From what I can tell, the behavior was originally added in this changeset by @jauborg.  I could not find any comments in the code or commit history explaining it.

  2. It was removed in this changeset also by @jauborg and also with no explanation.

  3. I asked this question as a comment on the commit and was told by @dmethvin it was the wrong place to ask.